Experimental generation of tripartite telecom photons via an atomic ensemble and a nonlinear waveguide

TL;DR

This paper demonstrates the experimental generation of telecom-band tripartite photons by combining atomic ensemble Raman scattering with nonlinear waveguide parametric down conversion, advancing multi-photon quantum state production for quantum communication.

Contribution

It introduces a novel hybrid approach combining atomic and nonlinear systems to generate genuine tripartite telecom photons, suitable for long-distance quantum networks.

Findings

Successful generation of photon triplets with strong temporal correlations.

First demonstration of combining different nonlinear processes and physical systems.

All photons are in the telecom band, suitable for fiber-based quantum communication.

Abstract

Non-classical multi-photon and number states attracts many people because of their wide applications in fundamental quantum mechanics tests, quantum metrology and quantum computation, therefore it is a longstanding aim to generate such states experimentally. Here, we prepare photon triplets by using the spontaneously Raman scattering process in a hot atomic ensemble cascaded by the spontaneous parametric down conversion process in a periodical poled nonlinear waveguide, the strong temporal correlations of these three photons are observed. Our experiment represents the first combination of the different order nonlinear processes and different physical systems, showing the feasibility of such composite system in this research direction. In addition, the all photons in the prepared genuine triplet are in telecom band make them be suitable for long-distance quantum communication in optical fibre.